The proposed investigation will include the identification of the metabolic pathways of oxalate metabolism in man and other mammals and the isolation, purfication and characterization of the enzymes involved. The contribution of each pathway and oxalate precursor will be evaluated in the light of potential regulation and control of the biosynthesis of oxalate in man: Each enzyme will be characterized with respect to their individual contribution to oxalate synthesis, location in tissues, specific inhibitors and activators, and potential for regulation or control. The ultimate goal is the prevention of Primary hyperoxaluria, kidney stones, and ethylene glycol toxicosis. BIBLIOGRAPHIC REFERENCES: Richardson, K.E. and Chou, J.Y. 1977. Effect of pyrazole and 4-methylprazole on ethylene glycol toxicity and metabolism. Fed. Proc. 36: 413. Fry, D.W. and Richardson, K.E. 1977. Isolation and characterization of glycolic acid dehydrogenase from human liver. Fed. Proc. 36: 717.